Suturing apparatus in the past have had an elongate shaft and a low profile distal clamping mechanism to facilitate their use through cannulas in less invasive surgery. These devices have typically included opposing jaws which clamp onto the tissue to be sutured. The end segment of the suture is pre-positioned and secured at the distal end of one jaw member. Beyond the clamping motion, the mechanism for passing a suture between the jaws and through the tissue incorporates a bendable flat needle. The bendable needle advances distally within the jaw member, bringing it in contact with a segment of the suture. The needle has a notch which engages and secures the suture to carry it forward.
This distal advancement of the bendable needle also results in the leading end of the needle to approach and engage a ramp in the jaw member, deflecting the bendable needle in a direction toward the opposing jaw. The bending of the needle requires a high force and results in excess strain on the notched needle component. Fracture and failure of the bendable needle is a concern.
Additionally, capturing suture reliably after being passed through the tissue is also a feature not currently offered by the existing technologies. The ability to throw a horizontal mattress stitch with the desired stitch width without having to remove and reload the instrument is currently an unmet need. Another area of improvement is the need to clamp onto thick tissue and reliably pass suture.
Further, extension of the needle beyond the opposing jaw member and potentially puncturing tissue or bone is also a safety concern with existing technologies. This limits the versatility of existing technologies to create desired stitch patterns, such as the modified Mason-Allen stitch.
It is thus desirable to provide improved systems and methods for passing suture through biological tissue that substantially reduces or eliminates the disadvantages and drawbacks associated with conventional, known systems and methods for the advancement and retention of suture through tissue.
It is therefore an object of the present invention to provide systems and methods for passing suture through biological tissue that shields local biological tissue and bone from damage.
It is another object of the invention provide systems and methods for passing suture through biological tissue that allows a needle and/or suture to be driven into and through body tissue in an antegrade and retrograde direction during endoscopic procedures.